1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
|
/* Starshatter: The Open Source Project
Copyright (c) 2021-2022, Starshatter: The Open Source Project Contributors
Copyright (c) 2011-2012, Starshatter OpenSource Distribution Contributors
Copyright (c) 1997-2006, Destroyer Studios LLC.
AUTHOR: John DiCamillo
OVERVIEW
========
Utility functions for generating random numbers and locations.
*/
#include "Random.h"
// +----------------------------------------------------------------------+
void RandomInit()
{
srand(timeGetTime());
}
// +----------------------------------------------------------------------+
Point RandomDirection()
{
Point p = Point(rand() - 16384, rand() - 16384, 0);
p.Normalize();
return p;
}
// +----------------------------------------------------------------------+
Point RandomPoint()
{
Point p = Point(rand() - 16384, rand() - 16384, 0);
p.Normalize();
p *= 15e3 + rand()/3;
return p;
}
// +----------------------------------------------------------------------+
Vec3 RandomVector(double radius)
{
Vec3 v = Vec3(rand() - 16384, rand() - 16384, rand() - 16384);
v.Normalize();
if (radius > 0)
v *= (float) radius;
else
v *= (float) Random(radius/3, radius);
return v;
}
// +----------------------------------------------------------------------+
double Random(double min, double max)
{
double delta = max - min;
double r = delta * rand() / 32768.0;
return min + r;
}
// +----------------------------------------------------------------------+
int RandomIndex()
{
static int index = 0;
static int table[16] = { 0, 9, 4, 7, 14, 11, 2, 12, 1, 5, 13, 8, 6, 10, 3, 15 };
int r = 1 + ((rand() & 0x0700) >> 8);
index += r;
if (index > 1e7) index = 0;
return table[index % 16];
}
// +----------------------------------------------------------------------+
bool RandomChance(int wins, int tries)
{
double fraction = 256.0 * wins / tries;
double r = (rand() >> 4) & 0xFF;
return r < fraction;
}
// +----------------------------------------------------------------------+
int RandomSequence(int current, int range)
{
if (range > 1) {
int step = (int) Random(1, range-1);
return (current + step) % range;
}
return current;
}
// +----------------------------------------------------------------------+
int RandomShuffle(int count)
{
static int set_size = -1;
static BYTE set[256];
static int index = -1;
if (count < 0 || count > 250)
return 0;
if (set_size != count) {
set_size = count;
index = -1;
}
// need to reshuffle
if (index < 0 || index > set_size-1) {
// set up the deck
int tmp[256];
for (int i = 0; i < 256; i++)
tmp[i] = i;
// shuffle the cards
for (int i = 0; i < set_size; i++) {
int n = (int) Random(0, set_size);
int tries = set_size;
while (tmp[n] < 0 && tries--) {
n = (n+1) % set_size;
}
if (tmp[n] >= 0) {
set[i] = tmp[n];
tmp[n] = -1;
}
else {
set[i] = 0;
}
}
index = 0;
}
return set[index++];
}
|